Efficient implementation of discrete cosine transform using recursive filter structure

We generalize a formulation for converting a length-2/sup n/ discrete cosine transform into n groups of equations, then apply a novel technique for its implementation. The sizes of the groups are 2/sup n-1/, 2/sup n-2/, ...2/sup 0/ respectively, while their structures are extremely regular. The realization can then be converted into recursive filter form, which is particularly simple for practical implementation.<
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